Positive muon-spin-relaxation (&#956;SR) has been used to investigate the evolution of spin dynamics in different high-pressure ice phases (e.g. ice-II, ice-VI, ice-VIII and high density amorphous ice) over the temperature range from 5 to 260 K with zero field and a fixed transverse magnetic field of 20 G. The results show that when a high external transverse field is applied to ices, the transverse spin relaxation rate is about 5 times smaller than that at the zero field. The temperature dependencies of the initial muon asymmetry spectra clearly show the phase transition and the muon site/state change in the all high-pressure ice phase (H2O and D2O) on heating to about 140 K.